1. Field of the Invention
This invention relates to a tire changing stand and more particularly to one which is powered for the purpose of breaking loose tires from wheel rims and also powered for revolving a tool to mount as well as de-mount a tire from the rim.
2. Description of the Prior Art
Tire changing stands having a center post for receiving a wheel rim are known in the art. For example, U. S. Pat. No. 3,685,565, issued Aug. 22, 1972 to Sorenson et al., shows such a stand. In the prior art stands, the wheel rim receiving surface is typically provided with an upstanding post over which the wheel rim is impaled when the rim and tire are placed on the receiving surface. In some cases, the post is threaded so that a clamp member can be engaged thereon and used to clamp the rim to the stand following the placement of the rim and tire onto the rim receiving surface.
Other prior art tire stands have featured rim engaging members which were offset from the center post and which engaged the tire rim at one or more locations about the rim periphery. The introduction of special or decorative wheel rims, such as those made of magnesium, aluminum, or using non-metallic material for decorative purposes, has created problems with respect to performing the tire servicing function without marring or otherwise harming the decorative rims. For example, holding a rim of magnesium on the tire changing stand by a threaded clamp member can result in gouging or otherwise marring the surface of the rim in the area immediately adjacent to clamping member.
In addition to the problem of marring decorative rims, many of the prior art tire changing stands were extremely complicated and bulky, making them unsuitable for portable use. As a result, it was not possible to use the units in the field at the location of a break down. Also, the fixed center post and base design of certain of the prior art designs made it extremely difficult to maneuver the wheel and rim into position on the stand. In particular, it was necessary to raise the wheel and tire over the center post to impale the tire. Since a large truck tire and rim can weigh in excess of 150 pounds, a great deal of effort was required.
The present invention has as its object the provision of a portable tire changing stand which is simple in design, light weight, and economical to manufacture.
Another object of the invention is the provision of such a tire changing stand which can be easily transported to the location of a breakdown on a highway or other field location.
Another object of the invention is the provision of a tire changing stand which can be operated without danger of damaging decorative rims and which has a shape and operation to facilitate handling large diameter tires and rims.